1. Field of the Invention
The present invention relates generally to roadway access devices and more particularly, to improved utility valve boxes, manholes and storm drains enabling ready vertical adjustment of the access devices and easy access to utility valves.
2. Description of the Related Art
Roads are periodically resurfaced due to the wearing away of the surface of the road by the constant passing of traffic. This resurfacing of a road usually raises the road height approximately 2 inches. Roadway access devices, including manholes and storm drains, which are within the area of a road surface have to be raised at some point either before or after resurfacing the road.
The common procedure in the preparation of roadway access devices for resurfacing begins with removal of sufficient amount of the road composition surrounding the installed device. This necessitates the use of a jackhammer along with its compressor apparatus and entails a very time consuming operation as the entire periphery of the access device must be cleared of contact with the road material; many access devices are several inches high thus requiring large amounts of material to be removed around them. This process is required when either replacing the existing access device with a different model or, before installing adaptor means or manipulating adjustment means to permit elevation of the same access device.
After provision is made to modify the plane of the access device and its associated lid or cover, the readjusted assembly is often sealed in place with concrete in order to fix it in its new position and to permit replacement of road material that had to be removed. It is not uncommon for the repositioning of a large access device to require up to three men and their heavy equipment and three hours' labor before the road is ready to be resurfaced.
In view of the labor and time now required to prepare existing access devices for a resurfacing job, the public is often subjected to at least protracted inconvenience and, frequently, less than safe driving conditions. This is evident when one considers that the time required to reposition the access devices throughout a repaving job of several miles can very well result in many of the repositioned access devices remaining in an exposed elevated condition for some time before repaving occurs.
There are currently three main methods for dealing with roadway access devices during paving projects. The first, primarily used in the eastern United States, involves raising the units prior to paving. The second method, used primarily in the west, involves raising the units after paving the road. The third method, used to deal with excessive asphalt buildup, involves lowering the road surface by grinding.
The fundamental problem with the first method is that the access devices are exposed for extended periods of time and suffer the daily pounding of normal vehicle traffic. This traffic often damages the access devices, resulting in the need to replace them at a significant cost.
The second method eliminates the problem of damaging the access devices prior to paving, but brings about the problem of locating the access devices following completion of the paving. Several contractors have tried to avoid this problem by measuring the location of the access devices prior to paving in order to easily expose them later. However, inaccurate measurements lead to far more destruction of the newly paved surface than is desirable. Even in the event the access devices were discovered easily after paving, the contractor would still be required to eliminate large amounts of asphalt to expose enough of the access device in order to raise it using existing methods.
Finally, the street grinding method causes problems similar to raising the access devices prior to paving (i.e. potential damage to the access devices) as well as problems related to the grinding method itself. The grinding tool can actually damage the valve boxes or can be damaged itself. To prevent this from happening, the grinder must be frequently raised and lowered which results in lengthy and costly operations. Additionally, once the grinding is completed, the remaining asphalt around the access devices must be removed manually.
Utility companies also encounter difficulties when people either accidentally or purposely tamper with their valves. Additionally, the utility companies often encounter difficulties in identifying the specifications of their own utility lines and it often requires much effort to discover necessary information.
Furthermore, existing utility valve boxes generally have an opening to provide access to the utility valve below. However, the valve is usually situated well below the surface of the road, making access difficult. Extended valve nuts have been created which raise the valve nut above its existing level. However, problems arise when a heavy load passes over the valve box, because the load is subsequently displaced to the utility line increasing the risk of damage. Additionally, natural elements and debris have a negative effect on valve nut operation.
What is desirable in the adjustment of devices such as manholes, storm drains or valve boxes is a minimal amount of necessary equipment or required use of force and time to alter its vertical position. Another desirable feature is to completely eliminate the excavation that has to be done to clear the device from the surrounding pavement so that it can be repositioned. Additionally, a desirable feature is that no matter which of the three methods described is used to resurface the road, there will be no interruptions to efficient paving operations. Another desirable feature would be a means of identification of the specifications of the valve contained beneath the valve box (i.e. location, valve type, pipeline pressure, material type and pipe size). Finally, a desirable feature would be a way of easily accessing valve nuts contained beneath utility valve boxes whereby the means of doing so would not cause undue loads to be placed on utility valves and piping systems while also keeping out unwanted debris and natural elements. Thus, a combination of these features can save many valuable man-hours and expense in the resurfacing of roads, sidewalks and the like. Every year, over three million of these access devices are raised with the average cost being about $300.00 per unit.
Numerous prior art devices have sought to address the issue of adjusting the height of roadway access devices. U.S. Pat. No. 5,095,667 issued on Mar. 17, 1992 to Ryan et al. discloses a telescopic manhole and storm drain installation which is conically shaped and utilizes a threaded vertical member to raise and lower the riser. The vertical adjustment of the riser is accomplished through the rotation of an externally threaded vertical riser member which is threadedly coupled with an internally threaded collar. The force that acts on the external threads of the riser is too great to be easily overcome.
U.S. Pat. No. 5,344,253 issued on Sep. 6, 1994 to Sacchetti discloses a telescoping manhole cover that is raised or lowered by adjusting a plurality of threaded bolts within the apparatus. The weight of the riser, as well as loads applied thereto is transferred to the threaded bolts. Additionally, in order for any adjustment to be made, excavation of the surrounding material would have to be performed. However, unlike the '253 invention, the weight of the riser and loads applied to the present invention are transmitted to a conical riser surface supported by surrounding fixed material such as concrete or asphalt, as will be better understood later.
World Patent No. 91/16504 issued on Oct. 31, 1991 to Kofel describes a vertically adjustable manhole cover which has two tubular elements threadedly engaged for vertical adjustment of the top portion. Again, the weight of the top portion and the loads applied thereto will be distributed to the threads and interlocking teeth of the adjustment assembly. Additionally, the top surface of the upper portion of the assembly is flush with the surface of the road. For any adjustment to be made, major excavation would have to be performed.
U.S. Pat. No. 4,337,005 issued on Jun. 29, 1982 to LeBaron taught the use of ring spacers to vertically alter the height of the riser, but a hoist means is necessary to raise the assembly in order to put the rings in place. Additionally, excavation of the surrounding material must be performed prior to raising the unit. It would be extremely difficult to get precise height adjustments using the method taught in LeBaron.
U.S. Pat. No. 4,325,405 issued on Apr. 20, 1982 to Christo discloses a valve box assembly having a valve box and a riser threadedly mounted in the valve box. The threads of the riser are external to the riser and therefore engage too great a frictional force in order to be turned easily. The external threads will collect dirt and debris which will prevent the unit from being raised. Further, because the unit has a protruding flange, excavation must be performed prior to raising the height of the device.
U.S. Pat. No. 5,209,601 issued on May 11, 1993 to Odill et al. discloses a manhole grade adjusting ring. Essentially, the ring is placed inside an existing manhole opening to raise the height of the manhole. The height adjustment of this device is determined by the manufactured height of the insert, thereby limiting field adjustment to the preset dimensions. The Patent to Odill does not teach the use of a threaded member for raising and lowering the height of the manhole or valve box as in the present invention.
U.S. Pat. No. 5,555,998 issued on Sep. 17, 1996 to Coppola discloses a removable lid for a gate valve which engages a bolt which extends through the pipe that the lid rests on. The drawback of the invention disclosed in Coppola is that the lid is easily removed by someone without authorized access.
Several patents disclose valve boxes or modifications thereof, but do not teach any means of adjusting the device. These include U.S. Pat. No. 4,874,105 (Valve Box) issued on Oct. 17, 1989 to Tetreault; U.S. Pat. No. 5,249,697 (Meter Pit) issued on Oct. 5, 1993 to McKinnon; U.S. Pat. No. 5,329,971 (Closet Flange Test Plug) issued on Jul. 19, 1994 to Condon; U.S. Pat. No. 5,525,007 (Sewer Construction) issued on Jun. 11, 1996 to Jones et al.; U.S. Pat. No. 5,333,750 (Durable Lightweight Meter Box) issued on Aug. 2, 1994 to McKinnon; and U.K. Patent No. 2,134,575A (Combined stop-cock chamber and surface box) issued on Aug. 15, 1994 to Evans.
A telescopic manhole assembly is described in U.S. Pat. No. 4,075,796 issued on Feb. 28, 1978 to Cuozzo and wherein vertical adjustment of the riser is achieved by rotating the assembly comprising a threaded flange. Cuozzo further illustrates cut-out portions or bores for a tool or locking member, but these are located at the top of a single, vertically walled riser sleeve. Additionally, once new pavement is added around the raised unit, subsequent adjustments require removal of the pavement before the unit can be moved.
Numerous patents have also addressed the idea of extended valve housings to make valve nut access easier. U.S. Pat. No. 3,537,471 issued on Nov. 3, 1970 to Houle discloses a valve extension assembly which allows the housing to telescope in response to a vertical loading for initial installation only. The invention in Houle does not teach a means for connecting the valve extension assembly to a utility valve box as described in the present invention; it is simply a means of directly accessing the valve beneath the sidewalk surface and is not capable of supporting massive loads as is the present invention.
U.S. Pat. No. 5,671,772 issued on Sep. 30, 1997 to Bliss discloses a vertically adjustable valve box for providing access to underground utility valves which comprises a housing which telescopes during initial installation and covers the utility valve and merely allows access to the valve by a long, cumbersome valve key. Access to the valve nut itself is not simplified in any way. Additionally, the invention in Bliss does not provide protection for the valve and is not coupled to a utility valve box which is capable of withstanding potentially great pressures.
Several patents have issued concerning valve housings which couple with valve utility boxes. In these patents, unlike the present invention, the valve remains far below the valve box and the housings merely provide a channel through which a serviceman could guide his tools. In addition, these inventions require significant excavation to raise the housing for pavement height changes. These include U.S. Pat. No. 5,634,488 (Modular Valve Service Box) issued on Jun. 3, 1997 to Martin, Jr.; U.S. Pat. No. 4,239,056 (Valve Service Box Having Means For Servicing Different Sized Valves Against Rotation) issued on Dec. 16, 1980 to Shope; Japanese Patent 4,238,920 (Duct Sleeve for Increased Port of Manhole) issued in August 1992 to Motoyuki Koga; and Japanese Patent 5,222,737 (Manhole Device of Underground Tank) issued in August 1993 to Yasuki Wada.
Several patents have issued concerning the general field of valve nut extensions, but not specifically housings for the valve nut extensions that couple to the utility valve box as in the present invention. These include U.S. Pat. No. 5,577,531 (Flood Protection Sewer Backflow Control Valve and Adapter Assembly) issued on Nov. 26, 1996 to Hayden et al.; U.S. Pat. No. 5,220,942 (Extensible Indicator Post for Valve Assemblies) issued on Jun. 22, 1993 to Garvin, Jr. et al.; U.S. Pat. No. 4,702,275 (Post Assembly for a Buried Valve) issued on Oct. 27, 1987 to Ballun et al.; U.S. Pat. No. 4,064,902 (Curb Box) issued on Dec. 27, 1977 to Swenson; U.S. Pat. No. 5,375,730 (Unloading valve for Hopper Car) issued on Dec. 27, 1994 to Bahr et al.; and German Patent No. 3,103,264 issued in August 1982.
Patents have disclosed lids for manholes and valve boxes, but are unlike the present invention. These include U.S. Pat. No. 4,726,490 (Safety Lid) issued on Feb. 23, 1988 to Bonnema et al.; U.S. Pat. No. 5,362,174 (Manhole Cover) issued on Nov. 8, 1994 to Yang.
None of the prior inventions known to the inventor in the field of valve nut height extensions incorporate a means of retaining necessary utility wires in order to prevent them from being pinched during servicing of the valve box device or the telescoping motion of the housing, thus resulting in costly repairs.
None of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention as claimed. Thus a telescopic roadway access device solving the aforementioned problems is desired.